Is it possible to send an order reference with PlaceOrder? (It is with the IB API.)
OrderRef:
It's part of miscellaneous order fields:
https://www.interactivebrokers.co.uk/en/software/tws/usersguidebook/configuretws/miscellaneous_defaults.htm
I use order references to track orders and it is the only way to check that an exit occurred was from a specific entry order with TWS when examing its execution log: GetExecList